Gas appliance metering device



June 1968 R. s. BAUMANN ETAL 3,338,962

GAS APPLIANCE METERING DEVICE Filed July 7, 1966 Jar/aims 5. Eawnamr v X16% United States Patent 3,388,962 GAS APPLIANCE METERING DEVICE RichardS. Baurnann, Glenbeulah, and Richard E. Linch,

Chilton, Wis., assignors to Western Industries, Inc., Milwaukee, Wis., acorporation of Wisconsin Filed July 7, 1966, Ser. No. 563,510 3 Claims.(Cl. 431344) ABSTRACT OF THE DISCLOSURE A portable pressurized gas fueltorch having a fuel metering device in the nature of a porous flowretarding element interposed in the fuel passage.

Background Portable pressurized gas fuel devices such as liquid propanetorches are well known in the art. In these devices, it is importantthat a proper flame be maintained while the device is operating on asupply of pressurized liquid fuel. Especially in the operation ofpropane torches or the like, it is important to provide a flow andpressure regulating device since the appliance will only burn properlyin an upright position, and flame sputtering and failure are encounteredwhen the torch or other appliance is tilted or inverted.

It is customary to provide an adjustable needle valve or the like forestablishing the proper torch or burner flame. Such adjustment of theflame is ordinarly made when the torch or burner and its attachedpressure cylinder are in an upright position. However, these devices arenot always used in such an upright position, and it is, of course,desirable that the flame adjustment should remain constant as initiallyadjusted regardless of the subsequent positioning of the device.

In order to accomplish continuity of flame adjustment, it is also commonpractice to provide a metering valve of one type or another between thepressurized cylinder and the needle valve adjustment in an effort toeliminate, or at least minimize, the possibility of an erratic orsputtering flame. Such metering valves are designed to perunit fuelpassage under regulated pressure to the burner for maintaining anapproximately constant flame, and without such metering valves, thetilting of the torch or other appliance or the partial emptying of thetank or fuel supply cylinder will cause the propane fuel to be broughtin contact with the needle valve and permit passage of the fuel withoutbecoming vaporized.

One type of metering or pressure regulating valve which has beenheretofore proposed consists of a spring balanced device housed withinthe body of a stem interposed in the fuel line between the supply sourceand the needle valve. While such prior metering valves have enjoyed acertain degree of commercial success, they nevertheless consist of aconsiderable number of parts requiring careful assembly, thus adding tothe complexity and cost of the device. Futhermore, these prior valveshave not proven entirely satisfactory in the overall operation of thetorch or other appliance due to their tendency to become unbalancedunder certain conditions of operation, as when the attached fuel tank isonly partially full.

Another type of metering valve or pressure regulating device which hasbeen heretofore proposed for pressurized gas fuel torches and similarappliances consists of a relatively simple diaphragm interposed in theline between the fuel supply and the needle valve. These diaphragm typepressure regulators consist of a thin disc hav- 3,388,962 Patented June18, 1968 ing metering apertures permitting passage of the pressurizedfuel for maintaining the desired flame in all positions of operation ofthe appliance, the diaphragm being prestressed by forming the same withan annular detent seat so as to provide a valving action. Such diaphragmtype pressure regulating valves have proven far less costly, lesscomplicated and easier to assemble than previous metering valvesembodying spring arrangements and the like, and they have proven highlyeffective in controlling and metering the desired amounts of fuel to thetorch or burner with less likelihood of flame failure or erratic actionupon tilting or inverting of the torch or partial emptying of the supplytank. However, these diaphragm valves do nevertheless require machineand stamping opertions as well as proper placement within a confinedarea and they are subject to fatigue through use.

Summary It is, therefore, an object of this invention to provide animproved device for properly metering pressurized gas fuel from a supplyof the fuel to the burner of the gas appliance under regulated pressureand flow conditions while obviating all of the objections anddisadvantages attendant prior devices intended for similar purposes.

Another object of the invention is to provide improvements in a liquidpropane torch or the like which assures maintenance of the desired torchflame regardless of the position of the appliance and which alsoentirely eliminates the need for any working parts whatsoever in thepressure and/ or flow regulation thereof.

Another object of the invention is to provide an extremely simple andeconomical pressure regulator for pressurized gas conducted from asupply source or tank to the burner in constant amounts without regardfor the position of the appliance in which the pressure regulator isincorporated.

A further object of the present invention is to provide a simplifiedfuel metering and pressure regulating device for a pressurized gas fueltorch or similar appliance which is entirely devoid of any moving partswhatsoever, which is readily positioned in the fuel line of theappliance, which requires no maintenance whatsoever and which is readilyaccessible for inspection and/ or replacement.

Still another object of the invention is to provide a gas meteringdevice in the nature of a sintered metal pellet constructed of amaterial having a particular size and density such that liquefiedpropane gas may pass therethrough, the flow of the gas being retardedsufficiently so that the rate of progress through the filter or meteringcapsule is only as rapid as the rate of its use at the burner, thuspermitting the appliance to operate at a constant predetermined andadjusted flame regardless of its posit-ion or fuel supply condition.

These and other more specific objects and advantages of the inventionwill be apparent from the following detailed description.

T he drawings A clear conception of the features constituting thepresent invention, and of the construction and operation of a typicalcommercial embodiment thereof, may be had by referring to the drawingsaccompanying and forming a part of this specification, wherein likereference characters designate the same or similar parts in the severalviews.

FIGURE 1 is an elevational view, partially in section, of a typicalpressurized gas fuel torch embodying the invention;

I) :1 -0 3 FIGURE 2 is an enlarged fragmentary transverse sectionthrough the fuel torch of FlGURE l; and

FIGURE 3 is a perspective view in section of one of the improved gasmetering filter capsules.

Detailed description Referring to the drawing, and particularly FIGURE 1thereof, the pressurized gas fuel appliance shown therein as embodyingthe invention is a typical liquid propane designated generally by thereference numeral It The torcn it} comprises a cylinder 12 containing asupply of liquid fuel under pressure, a valve body 14 threaded to acylindrical plug 16 carried by the cylinder 12, and a tubular neck orsupply pipe 18 equipped at its end with a nozzle 26.

To adjust the flame emanating from the nozzle 20', an adjustment valvehaving a knob 22 is provided, the adjustment valve being located betweenthe cylinder or supply tank 12 and the nozzle 20. This flame adjustmentvalve is shown as being in the form of a needle valve having a stem 24threaded as at 26 into the valve body 14 whereby the flow of fuel fromthe supply tank 12 to the nozzle 20 may be regulated by adjusting theknob 22.

For example, by turning the knob 22 in one direction, the nose portion28 of the needle valve will be seated against the seat 30 to close thepassageway 32 and shut off the supply of fuel from the supply tank tothe nozzle. By turning the knob 22 in the opposite direction,pressurized gas fuel will flow from the cylinder or supply tank 12through the passageway 32 and into the burner tube 18 to the nozzle unit20. The fiame issuing from the nozzle unit upon igniting the fuelissuing therefrom may then be adjusted by rotating the knob 22 to thedesired extent.

Referring more particular to FIGURE 2 of the drawing, the valve bodyunit 14 is illustrated as being screw threaded upon the cylindrical plug16, the plug 16 having a central bore 34 extending longitudinallytherethrough. Bore 34 in the plug 16 is adapted to receive a valve unit36 which is in the nature of the customary tire valve. This valve unit36 is spring controlled so as to remain closed prior to insertion of thestem portion 38 of the valve body unit 14 within the bore 34 of thecylindrical plug 16 so that the pressurized fuel supply cylinder or tankmay be sold or merchandized as a separate disposable unit. Uponinsertion of the stem 38 of the valve body unit 14 within the bore 34 ofthe cylindrical plug 16, the tire valve 36 is opened to thereby allowpressurized gas fuel to flow from the cylinder 12.

In accordance with the present invention, the stem 38 is screw threadedas at 40 directly into the valve body unit 14, the stem 38 beingprovided with a passageway 42 extending longitudinally therethrough. Theend of the assageway 42 of the stem 38 remote from the tire valve 36terminates in an enlarged counterbore portion 44 and received within thecounterbore 44 is a flow retarding or regulating element 46 havingminute orifices. This flow regulating element 46 may be in the nature ofa sintered metal pellet or equivalent structure having similarcharacteristics. The valve body 14 is accordingly formed with a fuelpassage therethrough as defined by the passageways 32, 2, and thecounterbore 44 thus forms a chamber intermediate the ends of the fuelpassage 32, 42 within which the porous sintered metal pellet 46 ishoused.

The sintered metal pellet 46 is formed of a material having a particlesize and density such that the liquefied propane gas under pressure inthe cylinder 12 may pass therethrough while being retarded sufficientlyso that the rate of progression through the pellet is only as rapid asthe rate of use at the burner nozzle 20. The sintered metal pellet 46,being porous, thus acts as a flow retarder .or regulator, and the rateof progression of the pressurized gas fuel through the element 46 isrelatively constant and does not vary appreciably with the pressureapplied to it. Thus the regulation of the How of the gas by the pelletinsures that the liquid propane, after passing through the pellet is nolonger subjected to high pressure since the rate of flow of the fuelinto the chamber 44, void 48 and passageway 32 is the same as the rateof flow past the needle valve 23 and through the tube 18 to the burnernozzle 20. This lack of pressure together with the heat conductivity ofthe metal pellet 46 causes any liquid to immediately vaporize and allowsoperation of the appiiance in any position without the introduction ofliquid fuel into the burner. The sintered metal pellet 46 is of a typewhich gives very close control over the flow rate therethrough and theprovision of numerous microscopic orifices makes resultant plugging ofall of the orifices highly unlikely thus providing a pressure regulatingdevice which is entirely devoid of moving parts and which eliminatesvarious machining and careful assembling operations.

It will, of course, be understood that the nozzle unit 20 may be of anyconventional construction which provides for the passage of fuel througha central orifice 50 and which also permits entrance of atmospheric airthrough orifices 52, the nozzle being provided with a cylindrical shield54 forming the combustion chamber. It should also be understood thatsuitable sealing means are provided for the stem portion 38 and theneedle valve 28, and the design of the torch or other appliance may bevaried without departing from the invention. Liquid propane torchesprovided with the improved flow or pressure regulating means have goneinto actual commercial use and have met with considerable success. Thesedevices have moreover reduced the cost of the torches or otherappliances while improving the efficiency of operation thereof, and thepressure regulating devices forming the subject matter of the presentinvention are not subject to fatigue failure as are other devicesintended for this purpose since there are no moving parts involved. Itis intended that specific descriptive terminology used herein shall begiven the broadest interpretation consistent with the disclosure, andvarious modifications within the scope of the invention may occur topersons skilled in the art to which the invention pertains. It shouldalso be noted that in order to obtain the full benefit of the minutepassageways in the flow regulating element 46, this ele ment is ofcylindrical shape and has one end thereof entirely exposed to the fuelpassage 42 with the other end thereof entirely exposed to the void 48which is in direct communication with the fuel passage 32.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointed out anddistinctly claiming the subject matter that is regarded as theinvention:

We claim:

1. A portable gas fuel device comprising, a container having a supply ofpressurized fuel and provided with a discharge opening, a valve membersecured within and normally closing said opening, a valve bodyreceivable by said member and having a portion cooperable with saidvalve member to open the same, said valve body having a fuel passagetherethrough communicable at one end with said container and providedwith a chamber of enlarged cross-section intermediate the ends of saidfuel passage, a burner nozzle communicating with the other end of saidfuel passage, a porous metal flow retarding and heat conductive elementhoused within said chamber and spanning said passage, and valve means insaid valve body adjustably manipulatable to open and close said fuelpassage and meter the fiow of fuel passing therethrough, said valvemeans being disposed between said chamber and said burner nozzle andsaid tlow retarding element having one end entirely exposed to the fuelpassage adjacent said container and the other end thereof entirelyexposed to the fuel passage adjacent said valve means.

2. A portable gas fuel device according to claim 1, wherein the porousflow retarding element is formed of sintered metal having numerousmicroscopic orifices.

5 6 3. A portable gas fuel device according to claim 2, References Citedwherein the microscopic orifices are of a size and num- UNITED STATESPATENTS ber such that liquid propane gas entering the flow re- 2 666 4801/1954 Peterson 158 33 tarding element is converted to gas and retardedsufii- 2:888:979 6/1959 Lindgren.

ciently so that the mass rate of flow of liquid into said 5 3 148 5229/1964 Court element is approximately the same as the mass rate of y Howof gas to the burner. JAMES W. WESTHAVER, Primary Examiner.

